Cutter-head



J. 0. HUMPHR'EYS'.

(No Model.)

CUTTER HEAD.

1ms70,542. Patented Sept. 27,1887.

WITNES S: 6 415W ATTORNEYS.

N. PEIERS. Phololiihogrghar. w:

UNITED STATES PATENT ()FFICEO JOHN G. HUMPHREYS, OF BRAXTON COURT-HOUSE, VEST VIRGINIA.

CUTTER-HEAD.

SPECIFICATION forming part of Letters Patent No. 370,542, dated September 27, 1887.

Application filed March 1'], i887.

To all whom it may concern:

Be it known that I, J onn CALDWELL HUM- rHREYs,of Braxton (lourt-Housein the county of Braxton and State of West Virginia, have invented a new and useful Improvement in Gutter-Heads, of which the following is a full, clear, and exact description.

This invention relates to rotary cutter-heads for planing lumber or other material; and it consists in certain novel constructions and combinations of parts, as hereinafter described, and pointed out in the claims.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

Figure 1 represents a longitudinal view of a rotary cutter-head embodying my invention. Fig. 2 is an end view of the same as seen from the left'hand side of Fig. 1, and Fig. 3 a transverse section thereof upon the line 00 a: in Fig. 1. Fig. 4 is an outer face or back view of one of the cutting-bits detached; Fig. 5, an inner face view,upon a larger scale,of a washer provided with a pocket used in securing and balaneingthe bits; and Fig. 6,a transverse section thereof upon the line 3 y in Fig. 5.

A is the cutter-bar, stock, or bit-holder of the rotary cutter-head, having a series of exterior convex surfaces, 11 and b, eccentric to the axis of the cutter-bar, and shaped so that the cutterbar or bit-holder, as viewed from its opposite ends,presents two threeleaved cams, each of which extends half the length of the cutter-bar, and so that the advance edges 0, which are the edges farthest removed from the axis of the cutter-bar of the cam-like surfaces or portions 2), are centrallyintermediate of the corresponding edgesc of the cam-like surfaces or portions 1), whereby the several edges 0 c divide a circle which would circumscribethem into six equal parts. These convex surfaces 1) 1) form the eccentric hearings, as in other cutter-heads differently constructed, for the cutting'bits B B, each of which is one-half the length of the cutter-bar, thus making the bits of one series intermediate of those of the other. The advance or cutting edges of said bits of course slightly overlap the edges 0 c of the portions 1) b, and, taking the two series of bits B B, divide the circle circumscribed by them into six equal parts.

Serial No. 213L215. (No model.)

With the several bits arranged as described only one bit will out at a time, thus requiring only about one-half the power to drive the cutter-head as if two bits were cutting simultaneously, and the bits project at such tangents and are so shaped on their backs that their outer surfaces back of the cutting-edges lie inside of the circle described by the cuttingedges, whereby the bits in cutting the wood work at an angle of from fifteen to twenty degrees, or thereabout, to it, instead of at an angle of forty-five degrees, as is generally the case, and do not drag or leave creases or ridges in the surface of the wood being dressed, but cut in contradistinction to scrapingit, and not only economize driving-power but wear and tear of the belts and machinery used to operate the cutter'head.

The bits B B are secured to their places on the cutter bar or stock by screws 0, arranged to enter said bar or stock and to pass through open-ended slots 0 and washers D in the bits, said washers being of irregular shape to prevent them from turning, and fitting within countersunk marginal portions f outside of the slots. Every facility is accordingly afforded for attaching and removing the hits as required and to hold them securely in place.

The several bits B Bare similarin construction or shape and size, so that they are interchangeable. This is important, as I have found from experience that the bits in rotary planing cutter-heads generally wear more in the middle of their lengths than at. their ends, which heretofore it has been usual to remedy by grinding. By using the two series of bits, however, and making the bits of the one series interchangeable with those in the other series-that is, the bitsB interchangeable with the bits B--I largely avoid this, as in interchanging or transposing said bits their outer ends become their inner ends on the cutter-bar. Furthermore, it isimportant, as is well known,

in rotary cutter-heads running at a high rate.

of speed, that the several bits should be of the same weight one with another. This, too, has usually been done by grinding the bits. To obviate this I construct each washer D with a pocket, g, on its inner side, in which may be placed shot or other weights 8, and thus virtually provide for making the several bits of the same weight, or, in reality, the portions of the cutter-head occupied by the several bits of like weight, thereby doing away with any irregularity in the motion or action of the cutter-head by an unequal distribution of its weight. By removing or adding weights 8 this adjustment can be very accurately effected without having resort to grinding the bits.

This arrangement of pockets in the washers- D, adapted to carry adjustable weights, is virtually the same as similarly and adjustably loading the bits themselves, and in some cases I make the bits also with poekets,in which to place shot or weights.

Having thus described my inventiomwhat I claim as new, and desire to secure by Letters Patent, is

1. A stock or bit-holder having two series of convex surfaces, 1) b, eccentric to the axis of the stock, each series extending half the length of the said stock, with the ad vanee edges 0 of one series of convex surfaces centrally intermediate the advance edges 0 of the other series of convex surfaces, substantially as herein shown and described.

2. The combination of the cutter bar or stock A, having a double series of eccentrieally-curved equidistant bit-bearing surfaces, Z) I), each series extending half the length of the cutter bar or stock, with the advance edges 0 of one series centrally intermediate the advance edges of the other series, the detachable and interchangeable bits B B, of equal length throughout, constructed to fit the said bearing-surfaces and adapted to cut at an acute angle, and means for detachably securing the bits to the cutter bar or stock, substantially as herein shown and described.

3. The washers D, provided with pockets 9, adapted to carry removable weights, in combination with the cutter-bar and a series of 0 bits arranged around said bar, and the screws 0, substantially as and for the purpose herein specified.

JOHN G. HUMPHREYS.

Witnesses:

E. A. BERRY, J. T. FRAME. 

